The present invention is based on a fuel injection valve, and on a method for manufacturing a valve needle of a fuel injection valve.
A fuel injection valve in which a valve needle is constituted from an armature, a tubular joining part, and a spherical valve closure element is already known from German Published Patent Application 38 31 196 or German Published Application Patent no. 40 08 675. The armature and the valve closure element are joined to one another via the tubular joining element, the joining part, to which the valve closure element is immovably joined via a weld bead, serving as the immediate closure element support. The joining part has a plurality of transversely extending flow openings through which fuel can emerge from an internal passthrough opening and flow, outside the joining part, to the valve closure element and to a valve seat surface coacting with the valve closure element. In addition, the joining tube has a longitudinal slit, extending over the entire length, through which, because of its large hydraulic flow cross section, fuel arriving from the inner passthrough opening can flow very quickly. Most of the fuel to be discharged already flows out of the joining part over its length. The remaining quantity emerges directly from the joining part only upon reaching the spherical surface, so that when viewed over the joining region between joining part and valve closure element, which extends over 360 degrees, there is a definite inhomogeneity in fuel distribution.